Quinone substituted phthalic acids



United States Patent 2,769,012 QUINONE SUBSTITUTED PHTHALIC ACIDS AlbertSchmelzer, Ko'ln-Mulhe'im, and Otto Bayer, Leverkusen-Bayerwerk,Germany, assignors to Farbenfabriken Bayer Aktiengesellschaft,Leverkusen, Germany, a corporation of Germany No Drawing. ApplicationJuly 15, 1952,

Serial No. 298,998

Claims priority, application Germany August 1, 195 1 5 Claims. (Cl.260-326) This invention relates to substituted phthalic acids and ismore particularly concerned with certain derivatives of phthalic acidand a process for the production thereof.

-It is well known that derivatives of phthalic acid are diflicult to beobtained on a practical scale.

It is therefore an object of this invention to provide a commerciallyfeasible method for producing substituted phthalic acids. Another objectis to provide certain novel derivatives of phthalic acid. Still otherobjects will appear hereinafter.

The above and other objects may be accomplished in accordance with theinvention by reacting a diazo com pound of 4-amino phthalic acid or itsderivatives with a member of the group consisting of quinones,acrylonitrile and similar vinyl compounds susceptible to polymerization.In general the reaction is carried out in a neutral or weakly acidmedium. In certain instances, it may be of advantage to add a coppercompound such as cupric chloride asa catalyst.

Taking a diazo salt of 4-amino phthalimide and benzoquinone as startingmaterials the reaction which occurs in accordance with the invention maybe written as follows:

OlNa CO NH N, nc1 co The derivatives of 4-amino phthalic acid which maybe used in our process include 4-amino phthalimide and the amides,esters and nitriles of 4-amino phthalic acid.

Among the quinones which will react to give useful products arebenzoquinone, chlorobenzoquinone, 2.3-dimethyl benzoquinone, tert.-butylbenzoquinone, phenyl benzoquinone, 04- and S-naphthoquinone,1.2-naphthoquinone-4-sulfonic acid, 1.4-naphthoquinone-6-carboxylic acidand -6-sulfonic acid, 1.4-dibenzene sulfoquinone diimide, 5.8-quinolinequinone, the indophenols etc. Vinyl compounds, other than acrylonitrile,susceptible to polymerization include acrylic ester, acrolein acetal,vinyl methyl ketone etc.

2,769,012 Patented Oct. 30, 195

The substituted phthalic acids obtainable by our invention are capableof a wide variety of reactions. Thus derivatives of phthalic acidcontaining a quinoid ring can be reduced and then alkylated or acylated.By catalytical hydrogenation and subsequent dehydration the quinoid ringcan be converted to a benzene nucleus. tion of the quinoid ring yieldsproducts which may under go the reactions of chloranil. The productsobtained from vinyl compounds as hereinabove described can also besubmitted to a great many reactions by known methods.

The invention makes it possible to produce a great number of substitutedphthalic acids in a simple and easily controllable manner. Thesesubstituted phthalic acids have been found to be useful intermediates inthe preparation of phthalocy-anines. Depending upon the constitution ofthe former, green and blue dyestufls of different solubility can beproduced.

The following examples in which the parts are by weight furtherillustrate the invention.

Example 1 Preparation of 4-phthalimido benzoquinone:

powder with the evolution of nitrogen. After stirring for one hour theprecipitate is sucked oil? and thoroughly washed with Water. The yieldamounts'to 139 parts (84% of theory) of crude material melting at217-218 C. After recrystallization from-glacial acetic acid the productmelts at 220221 C.

7 Example 2 7 Preparation of 4-phthalimido-u-naphthoquinone:

20.3 parts of 4-amino ph-thalimide suspended in 250 parts of water and135 parts of 37% hydrochloric acid are diazotized at 8-15 C. with asolution of 10 parts of sodium nit-rite in 30 parts of water. The diazosolution is neutralized by addition of parts of anhydrous sodium acetatein 250 parts of water. 30 parts of a-naphthoquinone are dissolved in 800parts of alcohol with heating and, if necessary, the solution isfiltered. The diazo solution is added dropwise to the above solution at22 24 C.

while stirring. Nitrogen is evolved. After stirring for about 16 hoursno more diazo compound is present. The yield amounts to 31.5 parts (83%of theory) of an orangebrown colored product melting at 320 C. afterrecrystallization from glacial acetic acid.

Chlorina- I 3 By cataly-tical hydrogenation and subsequent dehydration-the following compound may be obtained:

Example 3 Preparation of 4-phthalimido-p-naphthoquinone. 20.3 parts of4-amino phthalimide are diazotized as described in Example 2 andneutralized by addition of a sodium acetate solution. 30 parts offi-naphthoquinone are dissolved with heating in 790 parts of glacialacetic acid and 500 parts of water. Then the solution is cooled to. 20C. At this temperature the diazo solution is rapidly added. Nitrogen isevolved and a brown product precipitates. After stirring for one hour nomore diazo compound is present. The precipitate is sucked oflY,thoroughly washed with water and dried. The yield amounts to 29 parts(76% of theory) of a product melting at 313-315" C.

Example 4 Preparation of 4-phthalimido-18-naphthoquinone starting fromthe potassium salt of fi-naphthoquinone-4- sulfonic acid.

20.3 parts of 4-amino phthalimide are diazotized as described in Example2. 63 parts of the potassium salt of 1.2-naphthoquinone-4-sulfonic acid(purity: 83.6%) are dissolved in 5000 parts of water containing 125parts of anhydrous sodium acetate. The diazo solution is added dropwiseto the above solution at 28-30 C. A brown product precipitates with theevolution of nitrogen. After stirring for 12 hours no more diazo compound is present. The solution is worked up as described in Example 3.

Example Reaction of 4-amino phthalimide with acrylonitrile. 32.4 partsof 4-amino phthalimide are suspended in 200 parts of water and 95 partsof 37% hydrochloric acid are added While stirring. The diazotization iseffected at 05 C. with a solution of 14 parts of sodium nitrite in 30parts of'water. After removal of the surplus nitrous acid by aminosulfonic acid sodium acetate is added to the filtered diazo solutionuntil congo paper is no longer blued. Then a solution of parts ofacrylonitn'le in 158 parts of acetone is added to the above is obtained.By splitting off HCl with a tert. amine and subsequent saponificationCOOH HO OC.CH=CH -COOH is obtained.

Similarly acrylic acid and vinyl methyl ketone may be reacted with4-amino phthalimide.

Example 6 Preparation of 4 benzoquinonyl N B hydroxyethyl phthalimide. Asolution of 65 parts of 4-amino- N-B-hydroxyethyl phthalimide in 300parts of water and parts of 37% hydrochloric acid is diazotized at 5-10"C. with a solution of 22 parts of sodium nitrite in 50 parts of water.38 parts of finely powdered benzoquinone are suspended in a solution of120 parts of anhydrous sodium acetate in 1000 parts of water. The diazosolution is rapidly run into this suspension at 19-24 C. whilevigorously stirring. Nitrogen is immediately evolved and4-benzoquinonyl-N-fl-hydroxyethyl phthalimide precipitates. Afterstirring for 2 hours the yellowbrown precipitate is sucked OE andthoroughly washed with water. After recrystallization from alcohol thecompound melts at 157-159" C.

We claim:

1. A novel chemical compound in which a quinone radical is linked inthe, o-position to the 4-position of a phthalyl radical, said quinoneradical being selected from the group consisting of benzoquinonyl andnaphthoquinonyl, the phthalyl radical being selected from the groupconsisting of the radicals of phthalic acid, a lower alkyl phthalate,phthalimide and N-lower hydroxy alkyl phthalamides.

2. 4-phthalimido benzoquinone having the following structure:

3. 4-phthalimido-fi-naphthoquinone having the following structure:

OO-NH 4. 4-quinonyl-N-13-hydroxyethyl phthalimide of the formula:

5. A process for the synthesis of novel chemical compounds which processcomprises reacting phthalimide with an unsubstituted quinone selectedfrom the group consisting of benzoquinone and naphthoquinone.

References Cited in the tile of this patent Chem. Abst., vol. 23, p.2430, citing Covello, Univ. Naples, Rend. Accad. sci. Napoli 34 (3),149-51 (1928).

Chem. Abst., vol. 37, p. 109, citing Bettolo, Gazz Chem. ital. 71,627-35 (1941).

1. A NOVEL CHEMICAL COMPOUND IN WHICH A QUINONE RADICAL IS LINKED IN THEO-POSITION TO THE 4-POSITION OF A PHTHALYL RADICAL, SAID QUINONE RADICALBEING SELECTED FROM THE GROUP CONSISTING OF BENZOQUINONYL ANDNAPHTHOQUINONYL, THE PHTHALYL RADICAL BEING SELECTED FROM THE GROUPCONSISTING OF THE RADICALS OF PHTHALIC ACID, A LOWER ALKYL PHTHALATE,PHTHALIMIDE AND N-LOWER HYDROXY ALKYL PHTHALAMIDES.